فهرست مطالب

Caspian Journal of Environmental Sciences - Volume:17 Issue:3, 2019
  • Volume:17 Issue:3, 2019
  • تاریخ انتشار: 1398/06/10
  • تعداد عناوین: 8
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  • A. Salhi*, R. Bellaouchi, S. El Barkany, Y. Rokni, A. Bouyanzer, A. Asehraou, H. Amhamdi, A. Zarrouk, B. Hammouti Pages 189-198

    The purpose of the current study was to investigate total phenolic (TPC), total flavonoids (TF) and flavonols (FV) contents, as well as antioxidant and antimicrobial activities of different extracts of Pistacia lentiscus leaves. TP compounds were quantified by Folin-Ciocalteu, while antioxidant properties were evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH), radical scavenging assay (RSA), Ferric reducing activity power (FRAP) and β-carotene bleaching (βCB) assay. The antimicrobial activity was assessed against Gram-positive bacteria (Micrococcus luteus, Bacillus subtilis and Listeria innocua), Gram-negative bacteriaum (Escherichia coli) and fungi (Candida pelliculosa and Fusarium oxysporum albidinis). Overall, the ethanol fraction (EEPL) exhibited the highest TPC (70.4 ± 7.07 mg GAE g-1 powder), TF (32.06 ± 1.68 mg QE g-1 powder), FV (14.36 ± 1.68 mg QE g-1 powder) and RSA (IC50 = 5.34 ± 0.2 µg mL-1). Whereas, methanol extract (EMPL) displayed the highest FRAP (1.20 ± 0.02) and dichloromethane extract (EDPL) showed a high βCB (90.32 ± 2.98%). Furthermore, the antioxidant activities of extracts exhibited strong positive correlation with TP, TF and flavonols. The extracts obtained showed good inhibitory effect against most of the bacterial and fungal strains tested, suggesting their possible use as antimicrobial agents in medical or agro-industry sectors.

    Keywords: Pistacia lentiscus, Polyphenols, Antioxidant activity, Antimicrobial activity
  • M. Esfandiari*, H. Sodaiezadeh, M.A. Hakimzadeh Ardakani, M.H. Mokhtari Pages 199-211

    The purpose of this study was to assess some heavy metal (HM) concentrations in the soil and atmospheric falling dust along the Yazd highway, Yazd Province, Iran. The total concentrations of cadmium (Cd), cobalt (Co), copper (Cu), nickle (Ni), lead (Pb), zinc (Zn), iron (Fe) and manganese (Mn) in the dust and soil samples were measured using atomic absorption spectrophotometry after digestion with acid. The relationship between HMs in the falling dust was determined using correlation coefficients, principal component analysis and cluster analysis.  The mean concentrations of HMs in falling dust were higher than those of the nearby soils, except for Fe, Pb and Zn. The highest correlation between HMs in the falling dust and soil was associated with Cd and Fe as well as Cd and Ni with the correlation coefficients of 0.81 and 0.97, respectively. Based on the principle component analysis, cluster analysis and correlation coefficients, two resources were identified for HM concentrations in the falling dust. The measurement of enrichment factor exhibited that the region dust infiltration of metals on Mn (13.46), Zn (8.16) and Cu (5.21) are grouped in the severe enrichment class. Increasing industrialization and human activities lead to enter intensified levels of HMs into atmosphere. So, implementation of environmental standards and improvement of public transportation are necessary to reduce the level of pollutants entering the atmosphere.

    Keywords: Enrichment factor, Falling dust, Heavy metals, Multivariate analysis
  • H Khoshravan*, A. Naqinezhad, T Alinejad, Tabrizi, T Yanina Pages 213-226

    The rapid Caspian Sea level fluctuations have caused unstable conditions for coastal areas during the 20st and 21st centuries, and have led to significant losses for economical and social infrastructure. The main objective of this study was to assess the impact of the Caspian Sea level fluctuations on the environment of the Gorgan Bay coasts, which is a large, shallow inlet at the extreme south-east corner of the Caspian Sea. So that, studying required documentations have made it possible to become acquainted with the geographical, geological and environmental conditions of Gorgan Bay. The morphological conditions of coastal lines and diversity of coastal habitats were also assessed in field observations. The geometric structure of coast, their sediment types and the physicochemical properties of soils belonging to coastal habitats were evaluated by determining three transects and nine study sites in the spring and summer 2017. Changes in the coastline of Gorgan Bay were also processed using Land-Sat satellite imagery from 1977, 1995 and 2017. The results exhibited that the environmental vulnerability of the Gorgan Bay coasts depends on the morphological conditions of coastal habitats and alterations in the Caspian Sea level. So that, the plant and animal communities located in the most end of western part of the Gorgan Bay have faced serious challenges during the current century due to the decrease in the Caspian Sea level. Connecting canals between the Bay and Sea will also lose their discharge capacity and the Gorgan Bay will completely be dried up due to this decline. Emergence of large mudflats with sedimentary composition of sandy silt, which has created a very good potential for occurrence of haze, and also replacing the drought ecosystem, instead of the aquatic one, are other environmental events which are expanding vastly in the coastal areas of the Gorgan Bay.

    Keywords: Caspian Sea, Coasts, Environment, Fluctuations, Gorgan Bay, Morphology
  • M. Masoudi*, F. Behzadi, M. Sakhaei Pages 227-236

    In the present study, air quality analyses for NO2 were conducted in Tehran, capital of Iran. The measurements were taken in four different locations to provide average data in the city. The average concentrations were calculated diurnally, monthly and seasonally. Results exhibited that the highest NO2 concentration occurs generally in the early morning and early night, while the least in the afternoon and after mid-night. Monthly NO2 concentrations displayed the highest value in April, while the least in June and July. The seasonal concentrations exhibited the least amounts in summer, while the highest in autumn. Relationships between the air pollutant and some meteorological parameters were also calculated statistically using the daily average data. The wind data (velocity, direction), relative humidity, temperature, sunshine periods, dew point and rainfall were considered as independent variables. The relationships between pollutant concentrations and meteorological parameters were expressed by multiple linear and nonlinear regression equations for both annual and seasonal conditions using SPSS software. RMSE test displayed that the stepwise, among different prediction models, is the best option.

    Keywords: NO2, Air pollution, Meteorological parameters, Regression model
  • A. Salehzadeh*, F Nazarhaghighi, A.S. Naeemi Pages 237-248

    Chironomids (Diptera) include the most abundant group of macroinvertebrates. They are usually collected from aquatic environments for quality evaluation. Tolerant aquatic organisms such as Chironomids are more abundant in polluted sites. This note makes the Chironomids as an excellent bioindicators. This group is not characterized in Anzali Wetland as well. So that, the aim of this study was to recover and characterize chironomidlarvae in this wetland. Hence, Chironomidlarvae were collected on the seasonal basis from 13 stations in the wetland. The main characteristics for their identification were eye spot, mentum, ventromental plate, antenna, and ventral tubules. The mitochondrial cytochrome oxidase I (COI) gene was applied to simplify the identification of Chironomus species by polymerase chain reaction (PCR) and sequencing method. The nucleotide sequence alignments were used for construction of the phylogenetic trees based on maximum likelihood method. Six genera were identified in three subfamilies, including: Chironominae (1 genus), Orthocladinae (1 genus), and Tanypodinae (4 genera). Based on ventral tubules, the dominant population of Chironomus larvae found in this study, lie in thummi and plumosus types.  Five genera were reported for the first time from Anzali Wetland. The dominant genus was Chironomus.  These groups of larvae were ultimately identified as Chironomus plumosus reporting for the first time from the wetland. It was also found that the Chironomids diversity is higher than those described in few studies before, however, further studies are still needed.

    Keywords: Bio-indicator, Chironominae, Cytochrome oxidase I, DNA barcoding, macroinvertebrates
  • M. Yazarloo, H.G. Kami*, A.A. Bagherian Yazdi Pages 249-257

    We estimated age of the Caspian pond turtle, Mauremys caspicacaspicain Golestan Province with the skeletochronological method, using specimens collected by nets in natural habitats such as ponds and fish farms. In adult M. c. caspica, lines of arrested growth (LAGs) were clearly discernable in the phalangeal and fibula bone cross-sections. The median age of M. c. caspica in the examined Golestan Province population(n = 22) was calculated 9.6 years (4-12) in males (n = 10), and 10.16 years (4-13) in females (n = 12) for the first time. The maximum straight carapace length (SCL2) was in the range of 83.74–221.41 (mean ± SD = 178.39 ± 48.89) mm in males and 103.02–236.84 (193.52 ± 41.32) mm in female specimens. Significant correlation was found between body size and age (p < 0.001). No difference was found in age composition between the sexes. Our study showed that skeletochronological method can be successfully applied to the Caspian pond turtle based on the clear arrest of growth in the hibernation period.

    Keywords: Age, Caspian pond turtle, Golestan Iran, LAGs, Mauremys caspica, Skeletochronology
  • M. Nematpour, N. Habibzadeh* Pages 259-269

    The study aimed to investigate the attitudes of the villagers of Horand County, East-Azerbaijan about wildlife species with the focus on eight species and to determine the main causes of their conflict with the gray wolf. The data was collected using a semi-structured questionnaire during the spring and summer 2016. In 37 randomly selected villages, households were categorized as farmer-shepherd, shepherd, or farmer. In each village, 10% of the households belonging to each of the three groups were randomly selected and an interview was conducted with senior households.The results exhibited that three carnivorous species i.e. bear, hyaena and gray wolf were classified as problematic species along with boar, but the people were negative in their views toward hyaena and jackal than gray wolf and bear. The intensity of human-wolf conflict was positively influenced by an increase in respondents’ number of income sources, as well as by livestock disease-related losses. However, respondents’ increased awareness of wildlife was correlated with the decreased intensity of the human-wolf conflict. These results suggest that biodiversity conservation programs should prioritize attention to shepherd-farmers in managing the human-wolf conflict in Horand County.

    Keywords: Conservation attitudes, East-Azerbaijan, Horand County, Wildlife-human conflict, Gray wolf
  • B. Tolouei Nia, M.R. Aghamaali*, A. Asoodeh, M. Mehregan Pages 271-280

    This paper presents the findings of a basic study on biochemical characteristics and activity of lysozyme extracted from a commercially important fish, Caspian kutum, Rutilus kutum, Kamensky 1901. The enzyme was purified by the ammonium sulphate precipitation method and cationic exchange chromatography. Molecular weight of lysozyme was estimated as 15.8kDa by SDS-PAGE. The optimum pH and temperature were 6.0 and 45.0°C, respectively,while the Km and Vmax values were 0.00007g mL-1 and 200units min-1, respectively. Thermo-stability of the enzyme was low at the temperatures higher than 50°C. The enzyme activity increased in the presence of NaCl (1-50mM), KCl (1-50mM) and CrCl2 (1-5mM), then decreased at the higher concentrations. Furthermore, the enzyme activity significantly decreased in the presence of FeCl2 and CuCl2 (1-100mM), but not stable in the presence of MgCl2. SDS inhibited the activity, but the enzyme exhibited a good degree of resistance to urea. Fluorescence quenching was observed in the presence of FeCl2 and CuCl2. Emission intensities in the presence of NaCl, KCl, CrCl2 and SDS were elevated, while was negligible for the urea. Our results exhibitedthat NaCl and KCl are well-established salts for elevating the enzyme activity.However, the purified lysozyme did not display a moderate stability against others salts. Besides, the purified lysozyme from R. kutum was not heat stable. Therefore, some phenomena such as water hardness and warming can exert negative effects on the innate immunity of the fish. So, the enzyme structure can be made more stable by medium engineering through changing the salt composition of aqueous solution.

    Keywords: Characterization, Lysozyme, Rutilus kutum